Abigail Falk

Maintenance and salvage of arteriovenous fistulas.

PURPOSE To describe the number and type of percutaneous interventions required to promote maturation and maintain patency of hemodialysis fistulas. MATERIALS AND METHODS One hundred fifty-four hemodialysis fistulas were created in 146 patients by a single surgeon between August 2001 and March 2005. There were 88 male patients (60%), and the median age of the group was 66 years. The records of all percutaneous procedures performed on these patients were retrospectively reviewed. The medical records from the hemodialysis treatment centers were also reviewed to assess fistula patency during the follow-up period. RESULTS Of the initial 154 fistulas created, 112 (73%) were successfully used for hemodialysis. One hundred thirteen procedures were performed to promote maturation of 65 fistulas (1.7 procedures per fistula), including 66 venous angioplasty procedures, 16 arterial angioplasty procedures, ligation of 21 venous side branches, five thrombectomy procedures, three banding procedures, and two other procedures. Only 48 of these nonmaturing fistulas (74%) became functional. Sixty-three mature fistulas required 209 procedures (3.3 procedures per fistula, 1.75 procedures per access-year) to maintain vascular access patency. These included 174 venous angioplasty procedures, 18 arterial angioplasty procedures, 14 thrombectomy procedures, ligation of three venous side branches, and two stent placement procedures. The mean follow-up period for all 154 fistulas was 317 days (range, 12-1,138 days). Primary patency rates at 90, 180, and 360 days were 71%, 69%, and 64%, respectively, and secondary patency rates were 73%, 72%, and 68%, respectively. CONCLUSIONS Percutaneous procedures can promote maturation and maintain patency of arteriovenous fistulas. However, despite numerous procedures to promote maturation, only 74% of nonmaturing fistulas became functional.

Thoracic duct injury associated with left internal jugular vein catheterization: anatomic considerations.

Ultrasound (US)-guided cannulation of the internal jugular vein (IJV) has become the preferred approach for venous access as a result of its higher success rate and lower incidence of complications. This report describes a case of thoracic duct injury during US-guided left IJV catheterization. The normal and variant anatomy of the thoracic duct in the neck is illustrated.

A Randomized Prospective Study Comparing Outcomes of Angioplasty versus VIABAHN Stent-Graft Placement for Cephalic Arch Stenosis in Dysfunctional Hemodialysis Accesses

PURPOSE To determine if postintervention cephalic arch stenosis (CAS) primary patency and access circuit patency are superior with the VIABAHN stent graft compared with angioplasty at 3, 6, and 12 months. MATERIALS AND METHODS All patients presenting with dysfunctional hemodialysis accesses with CAS over a 4-year period were assessed for inclusion in a randomized prospective study. A total of 14 patients were recruited across three centers. All patients had mature brachiocephalic fistulae. Five were randomized to undergo percutaneous transluminal angioplasty and nine to undergo stent-graft placement. Patency of the treated cephalic arch was assessed with transonic flow and/or follow-up fistulography. Variables assessed were diabetes, previous interventions performed on the access, access age and side, and sex. Patency was determined with Kaplan-Meier estimation. RESULTS Anatomic and clinical success was obtained in all interventions. Mean patency intervals were 100 days in the PTA group and 300 days in the stent-graft group. Primary access circuit patency rates at 3, 6, and 12 months were significantly different: 20%, 0%, and 0% for PTA and 100%, 67%, and 22% for stent grafts (P < .01). Primacy target lesion patency rates at 3, 6, and 12 months were also significantly different: 60%, 0%, and 0% for PTA and 100%, 100%, and 29% for stent grafts (P < .01). No complications or adverse events were observed. CONCLUSIONS Treatment of CAS with the VIABAHN stent graft appears to provide statistically superior primary patency rates compared with balloon angioplasty.

Conversion of Temporary Hemodialysis Catheters to Permanent Hemodialysis Catheters: A Retrospective Study of Catheter Exchange versus Classic de novo Placement

Many clinicians believe that de novo access is required when converting temporary hemodialysis (HD) catheters to long‐term or permanent catheters. However, since vascular access sites are at a premium in the dialysis patient, it is important to preserve existing central venous catheters and conserve future access sites. In this retrospective study, data from 94 patients referred to interventional radiology for placement of long‐term, tunneled HD catheters between July 2001 and September 2002 were reviewed. The study group consisted of 42 patients in whom the temporary catheter was exchanged for a peel‐away sheath and a tunneled catheter inserted using the existing venous access site. The control group included 52 patients who received traditional de novo placement of permanent catheters. Based on available follow‐up data, we report a 100% technical success rate, with 72% patency at 30 days in the study group (n = 32; mean age 58 years). By comparison, de novo catheter placement (n = 35; mean age 59 years) yielded a 100% technical success rate, with 83% patency at 30 days. The overall infection rate was 0.30 per 100 catheter‐days (total 3036 catheter‐days) and 0.36 per 100 catheter‐days (total 3295 catheter‐days), respectively (χ2 = 0.64, p ≥ 0.05). There was no incidence of exit site infection, tunnel infection, or florid sepsis in either group. Likewise, no stenosis or bleeding complication was noted. Thus conversion of a temporary HD catheter to a tunneled catheter using the same venous insertion site is safe, does not increase the risk of infection, and allows conservation of other central venous access sites.

Aortic intimal dehiscence: a complication of percutaneous balloon fenestration for aortic dissection.

A patient with acute type B dissection and a tube configuration of the intimal flap presented with signs of advanced mesenteric and renal ischemia as well as decreased pulses in the lower extremities. The patient was referred for emergency percutaneous fenestration of the abdominal aorta as a salvage procedure and a possible bridge to later surgery. After fenestration, femoral pulses became transiently stronger and then disappeared. The patient died after exploratory laparotomy. Postmortem examination demonstrated dehiscence of the infrarenal abdominal aortic intima with occlusion of the aortic bifurcation.

A Prospective, Randomized Study of an Expanded Polytetrafluoroethylene Stent Graft versus Balloon Angioplasty for In-Stent Restenosis in Arteriovenous Grafts and Fistulae: Two-Year Results of the RESCUE Study

PURPOSE To assess the safety and efficacy of an expanded polytetrafluoroethylene stent graft versus balloon angioplasty for the treatment of in-stent restenosis in the venous outflow of hemodialysis access grafts and fistulae. MATERIALS AND METHODS Two hundred seventy-five patients were randomized at 23 US sites to stent-graft placement or percutaneous transluminal angioplasty (PTA). Primary study endpoints were access circuit primary patency (ACPP) at 6 months and safety through 30 days; secondary endpoints were evaluated through 24 months. RESULTS ACPP at 6 months was significantly higher in the stent-graft group (18.6%) versus the PTA group (4.5%; P < .001), and freedom from safety events (30 days) was comparable (stent graft, 96.9%; PTA, 96.4%; P = .003 for noninferiority). The separation in ACPP survival curves remained through 12 months (stent graft, 6.2%; PTA, 1.5%). Treatment area primary patency (TAPP) was superior for the stent-graft group (66.4%) versus the PTA group (12.3%) at 6 months (P < .001), with a survivorship difference in favor of stent-graft placement maintained through 24 months (stent graft, 15.6%; PTA, 2.2%). ACPP and TAPP for the stent-graft group were better than those for the PTA group when compared within central and peripheral vein subgroups (P < .001). In central veins, TAPP was 13.6% in the stent-graft group versus 4.3% in the PTA group at 24 months (P < .001). CONCLUSIONS Stent-graft use provided better ACPP and TAPP than PTA when treating in-stent restenosis in patients receiving dialysis with arteriovenous grafts and fistulae.

Tenecteplase in the Treatment of Thrombosed Hemodialysis Grafts

A pilot study was carried out to prospectively evaluate the efficacy and safety of Tenecteplase (TNKase) using a modified ’lyse and wait” technique with percutaneous transluminal angioplasty (PTA) to treat thrombosed hemodialysis arteriovenous grafts (AVG)s. Seven patients with eight hemodialysis AVGs were treated and followed up to 1 year. Dosing included 1 mg TNKase and 3,000–4,000 U of heparin. Technical and clinical success rates were 100% and 88%, respectively. No major complications occurred. Primary patency rates at 30, 90, and 180 days were 62%, 50%, and 33%, respectively. TNKase, used in this fashion, may be comparable to alteplase and reteplase for safe and effective thrombolysis of PTFE dialysis grafts.

Suggested Guidelines for Performing Procedures in Patients with Chronic Kidney Disease in Outpatient Centers

Maintenance of hemodialysis vascular access is increasingly performed on an outpatient basis by physicians trained in interventional techniques. The adoption of guidelines by national reputable organizations will help identify patients eligible for such outpatient treatments and help optimize the safety and efficacy of their procedures in the outpatient setting.

The Immature or Failure to Mature Fistula

One of the inherent problems with hemodialysis fistula creation and hence bias towards creating them is a relatively high failure rate of maturation of 25–33% within North America [1]. This happens despite preoperative screening for selection of the best artery and vein [2, 3]. With the introduction of the Fistula First Initiative, there has been increased emphasis on primary placement of an autogenous hemodialysis fistula within the United States with a correspondent increase in number of nonmaturing fistulas and interest in techniques to salvage them.

Re: Pulmonary Steal from a Left Internal Mammary Artery Bypass Treated with Transcatheter Embolization

predisposing factor for infection is a large residual cyst cavity filled with fluid and fragments of membranes, leading to abscess formation and sepsis. It is usually successfully treated by percutaneous catheter drainage with appropriate antibiotic therapy. However, occasionally this treatment alone may be insufficient, and the abscess drainage continues for a prolonged period. In this instance, repeated intracavitary injections of sclerosing agents such as 10% povidone-iodine (Betadine) or 96% ethanol may be required for complete healing [3]. It is important to remember, that prior to injection of these sclerosing agents, an abscessogram should be performed to exclude a bilio-cystic fistula. If such a fistula is found, injection of a sclerosing agents is contraindicated because of the risk of sclerosing cholangitis which may lead to biliary cirrhosis.